Very Short Questions

A sharp knife has smaller area at its edge than a blunt knife. When a force is applied on the knife, The pressure exerted by the edge of sharp knife is more than the pressure exerted by the blunt knife during cutting. Due to this reason, cutting with a sharp knife is easier than cutting with blunt knife.

When a man stands with one foot the area of surface where the force is applied is decreased and as a result the pressure is increased because keeping the force constant, the pressure is inversely proportional to the area of surface that receives the force.

The pressure is defined as “the force acting perpendicularly per unit area”. The pressure is defined as the perpendicularly applied force on a unit area. The SI unit of pressure is N/m2. It is also called Pascal (pa).

The two aspect of our daily life where pressure theory is used are: 1. Application of pressure cooker to cook our food. 2. The flow of water is highest at the tap connected at the lowest level from the tank than the subsequent taps above it.

As we know pressure is inversely proportional to the area on which the force is applied. When area is increased (keeping the force constant) the pressure is decreased as the same foce now has to act on large area so force gets dispersed.

When a man stands on one foot the surface area on which is force is acting is smaller compared to when he is standing on two foot. So, as the area is decreased the pressure applied is increased (because force is inversly proportional to the area). So, A man exerts more pressure under his foot when he stands with one foot than when he stands on two foot.

As the knife gets sharper the surface area of the knife's cutting edge have very less surface area. When the surface area is reduced the pressure applied with the same amount of force is increased as pressure is inversely proportional to the surface area. So the knife with sharp edge (having less surface area) cuts easily tahn the blunt ones (having more surface area).